Akao Instr Sets exported to SF2 do not write dynamic ADSR information about vgmtrans HOT 2 OPEN

Thanks for the detailed report. I'll take a look when I have the chance. I think you might already understand this, but Sustain Rate isn't a concept in SF2 and DLS. As a workaround, the PSX ADSR conversion code (which is over 15 years old and not the greatest), checks if the decay stage is effectively unused, and if so, attempts to implement the sustain rate using decay (but only if the sustain rate is a negative value - yes it can increase amplitude as well). At any rate, this is very possibly what you're seeing here, and yeah it's probably buggy even for what it's attempting to do. But bear in mind that SF2 and DLS can't represent the PSX SPU envelope entirely accurately.

from vgmtrans.

@mikelow thanks for the response and the informative explanations! Yes, I'm vaguely aware of the envelope parameters that the PSX SPU has to offer, and that it definitely has more than the basic ADSR parameters that SF2 has to offer. So what I would hope would occur on SF2 export would be an approximation of what the instruments are doing on the SPU, rather than something exact. Unfortunately, I can't find much documentation on the Akao instrument format to get more information about what the above bytes corresponding with ADSR parameters correspond to in terms of seconds - however in its current implementation, every ADSR acts essentially as a gate, so instruments that have looping samples and rely on decays (like guitars and harps) are rough.

from vgmtrans.